1. Field of the Invention
The present invention relates to a platform attachment for providing a horizontal platform mounted upon a ladder.
2. Description of the Prior Art
A variety of work platforms for use in connection with ladders has been proposed in the prior art. Each of these platforms includes a differing structure which provides unique and advantageous features associated therewith. The present invention is directed at a platform attachment for a ladder which provides a platform which is extremely stable and readily accessible once erected, and also provides for a quick and simple means for mounting the platform.
A supporting means for ladders and scaffolds is disclosed in U.S. Pat. No. 2,680,554, issued to Dakin on June 8, 1954. In one embodiment, the Dakin device comprises a pair of interconnected arms which are pivotally attached to sleeve-like brackets which are mounted to the side rails of the ladder and rest upon a rung of the ladder. At the top end of each of this pair of arms is pivotally connected an arm which at its opposite end is pivotally mounted to a sleeve-like bracket which is mounted to a side rail of the ladder and rests upon a second, higher rung of the ladder. The ladder arms provide a horizontal surface upon which a scaffold or similar platform may be supported.
A ladder work platform is disclosed in U.S. Pat. No. 2,641,511, issued to McClure on June 9, 1953. The McClure platform includes a pair of posts which are mounted upon a ladder rung by retaining the rung within a bracket which is bolted to each post. A cross member connects the tops of the posts, and a platform is mounted upon the cross member and upon a rung of the ladder. The platform extends from the post to the ladder and beyond the ladder to a location at which additional support members are connected between the platform and a third rung of the ladder positioned above the platform. In U.S. Pat. No. 1,593,366, issued to Singer on July 20, 1926, there is disclosed a similar platform attachment which includes a pair of posts mounted upon a step of a ladder and a platform mounted upon and extending between the upper ends of the posts and a second and higher rung of the ladder. Yet another similar device is diclosed in U.S. Pat. No. 2,606,079, issued to White on Aug. 5, 1952. The White device further includes the provision of bifurcated lower ends of the posts within which bifurcations the ladder rung is received. In U.S. Pat. No. 1,645,879, issued to Skeels on Oct. 18, 1927, there is disclosed a platform support which includes a platform resting at one end upon a ladder rung and including a bracket which secures and supports the opposite end of the platform upon a second and higher rung of the ladder.
An adjustable ladder attachment is disclosed in U.S. Pat. No. 2,459,437, issued to Kreissler et al. on Jan. 18, 1949. In the Kreissler attachment, a platform is provided which includes a lip which engages a side of a ladder rung when the platform is rested upon the rung. A first pair of brackets are located on the underside of the platform near the platform lip and a first pair of arms are pivotally attached to the respective brackets. The first pair of arms are positioned to extend along the ladder and rest upon a lower ladder rung, with a rod interconnecting the lower ends of the first pair of arms. A second pair of brackets are located on the underside of the platform and spaced apart from the first pair of brackets. A second pair of arms are pivotally attached to the second pair of brackets and include a plurality of notches at their lower ends which are oriented to receive the interconnecting rod therein. By appropriate selection of the notches to receive the interconnecting rod, the angle of the platform may be varied to correspond to a varying angle of incline for the ladder.